1. Field of the Invention
The present invention relates to a multi-channel pulse width modulation (PWM) apparatus.
2. Background of the Related Art
A multifunctional apparatus such as “a DVD receiver” includes an optical disc apparatus and an A/V (Audio/Video) receiver integrated as one body. The optical disc apparatus reads high-quality video and audio signals recorded on an optical disc such as a CD or DVD, and reproduces the audio signal in the form of a PCM (Pulse Code Modulation)—based multi-channel audio signal. The A/V receiver modulates the PCM-based multi-channel audio signal into a PWM (Pulse Width Modulation)—based multi-channel audio signal, and amplifies/outputs the PWM-based multi-channel audio signal through a plurality of speakers.
However, as described above the related art DVD receiver has various disadvantages. For example, the PWM-based multi-channel audio signals generate noise, particularly between adjacent signal processing paths. Further, such generated noise can be significant at a time of a rising edge and a falling edge of data signals to deteriorate sound quality. In addition, the PWM-based multi-channel audio signals have system level gain control identically across channels, so a user cannot independently selectively control gain of an audio signal of a desired channel. Also, a system overload condition signal is a system level control across channels to stop the PWM when system load exceeds a reference value. Accordingly, additional noise can be generated by the PWM apparatus.
The above references are incorporated by reference herein where appropriate for appropriate teachings of additional or alternative details, features and/or technical background.